Brooks, David (2011-03-08). The Social Animal: The Hidden Sources of Love, Character, and Achievement (pp. 88-89). Random House, Inc.. Kindle Edition.

Expertise is about forming internal connections so that little pieces of information turn into bigger networked chunks of information. Learning is not merely about accumulating facts. It is internalizing the relationships between pieces of information. Every field has its own structure, its own schema of big ideas, organizing principles, and recurring patterns—in short, its own paradigm. The expert has absorbed this structure and has a tacit knowledge of how to operate within it. Economists think like economists. Lawyers think like lawyers. At first, the expert decided to enter a field of study, but soon the field entered her. The skull line, the supposed barrier between her and the object of her analysis, had broken down. The result is that the expert doesn’t think more about a subject, she thinks less. She doesn’t have to compute the effects of a range of possibilities. Because she has domain expertise, she anticipates how things will fit together.”